During assembly of a fuel injector nozzle, certain components must be properly aligned. For example, it may be desirable for injection holes within a nozzle tip to be arranged in a desired orientation relative a nozzle casing. Thus, when the nozzle casing is assembled to an engine in a predetermined orientation, the injection holes will be arranged in a desired manner relative the engine, for example toward a particular portion of a combustion chamber of the engine.
In one known apparatus, a fuel injector nozzle includes a two-piece tip assembly. A first generally cylindrical tip member includes first and second ends. The first end has fuel injection holes therein and extends outward from a nozzle casing. The second end is held within the nozzle casing and engages a generally cylindrical second tip member, which is completely arranged within the nozzle casing. The second tip member is held in a predetermined rotational configuration relative the nozzle casing, for example via a pin-and-slot arrangement. The first and second tip members are also held in rotational alignment with respect to each other via a pin-and-slot arrangement. For example, the first and second tip members each have a slot formed therein for receipt of a pin. During assembly, the first tip member is rotated relative the second tip member until their respective slots are aligned. Then a pin is inserted into the slots to secure the tip members in rotational alignment with respect to each other.
While the fuel injector arrangement described above may be effective for achieving rotational alignment of a fuel injector tip relative a nozzle casing, certain improvements may be desired. For example, it may be desirable to reduce the overall size or weight of a fuel injector nozzle. Thus, injector walls may be thinned, and injector components shrunken. As injector walls are made thinner and injector parts are made smaller, certain pin-and-slot arrangements, or other similar arrangements, may become less desirable. Moreover, it may be desirable to provide a robust tip alignment mechanism suitable for a simple assembly process. It may further be desirable to provide a nozzle assembly with fewer parts.
The present invention is directed to overcome or improve one or more characteristics associated with prior fuel injector nozzles.